PSLE
Three men, Lon, Abe and Rey had the same number of notes. Abe and Lon each had of mix of $100-notes and $10-notes. Abe had 5 $10-notes while Lon had 12 $10-notes. Rey had only $100-notes.

1. Of the three men, who had the least money? 
2. What was the difference in the total value of Abe and Lon's notes? 
3. Lon used all his $100-notes to buy a present. Rey then had $1680 more than Lon. How many $100-notes did Rey have?

(a)
The three men had the same number of notes.
$10-notes have a lower denomination than $100-notes.

Lon had more $10-notes than Abe while Rey had only the $100-notes.  

Since Lon had the most number of $10-notes, he had the least money.

(b)
Difference in the number of notes of different values
= 12 - 5
= 7

Difference in the value of $100-note and $10-note
= 100 - 10
= $90

Difference in the total value of Abe's and Lon's notes
= 7 x 90
= $630

(c)
Value of $10-notes that Lon had left
= 12 x 10
= $120

Total value that Rey had
= 1680 + 120
= $1800

Number of $100-notes that Rey had
= 1800 ÷ 100
= 18

Answer(s): (a) Lon; (b) $630; (c) 18